Foaming cosmetic compositions must satisfy a number of criteria including cleansing power, foaming properties and especially mildness/low irritancy with respect to the skin, hair and the occular mucosae.
Skin is made up of several layers of cells which coat and protect the keratin and collagen fibrous proteins that form the skeleton of its structure. The outermost of these layers, referred to as the stratum corneum, is known to be composed of 250 A diameter protein bundles surrounded by 80 A thick bilayers of epidermal lipids and water. Surfactants can penetrate the stratum corneum membrane and, by delipidization (i.e. removal of the lipids from the stratum corneum), destroy its integrity. This destruction of the stratum corneum bilayers can lead to dry rough skin and may eventually permit the surfactant to interact with the viable epidermis, creating irritation.
Ideal cosmetic cleansers should cleanse the skin or hair gently, causing little or no irritation without defatting and or drying the skin and without leaving skin taut after frequent use. Most lathering soaps, liquids, gels and bars are limited in this respect due to their use of surfactants.
Thus a need exists for foaming cosmetic compositions which will produce a foam which is abundant, stable and of high quality (compactness), which are effective skin and hair cleansers and which are very mild to the skin, hair and occular mucosae.
Liquid and solid bar compositions based on soap and/or synthetic surfactants are commonly used for cleansing the human body. To achieve adequate lather when diluted with water, these require a higher level of surfactant than may be necessary to provide adequate cleaning. This excess surfactant can be irritating to the skin and is put into the environment unnecessarily. The use of foams for cleaning skin has usually been reserved for specialty products that are used without rinsing. See, e.g., U.S. Pat. No. 3,962,150, Viola, issued Jun. 8, 1976, incorporated herein by reference. There has been little or no recognition of the mildness and environmental advantages that can be derived from the use of such products for general cleansing.
Personal cleansing compositions exist today in a variety of product forms. These forms range from emollient and lathering cleansers to cold creams and bar soaps. The commonality of each of these forms is that they always contain some level of soap and/or synthetic surfactant components (detergents).
Surfactant based cleansing systems typically contain a combination of surfactant and polymer components. The polymer additions are primarily recognized, and have been extensively documented, for their ability to provide skin and/or hair conditioning properties. These polymers are further recognized for their ability to reduce the inherent skin irritancy properties of surfactants. The polymer components reduce skin irritation by developing a protective barrier on the skin surface that inhibits delipidization and the resultant barrier destruction properties of surfactants. Barrier destruction has been documented to be a primary contributor to dermal irritation. The polymer components are further recognized for their ability to enhance the foaming properties of emollient and lathering cleanser forms as well as bar soaps. Polymers are known to alter the physical properties (i.e. density/stability) and textural properties (i.e. creaminess) of foams. Combinations of polymers and surfactants have been, and continue to be used today to produce personal cleansing compositions that provide the cleansing and foaming properties necessary to attain consumer appeal. However, it has not before been recognized that compositions which do not contain a cleansing level of surfactant can provide very mild cleansing compositions.
The present invention relates to aerated personal cleansing compositions that provide cleansing efficacy without the use of any surfactant components. The polymer(s) system can also include at least one anionic, nonionic, or amphoteric alkyl substituent to the backbone of the polymeric carbon chain. Because of the absence of any irritating surfactants, these compositions are extremely mild to skin and/or hair.
A further object of the invention is to deposit hydrophilic agents, such as sunscreen agents to skin and/or hair. Such deposition of sunscreen agents would provide protection from the chronic damaging effects associated with ultraviolet exposure. The instant invention further encompasses the use of cosmetic astringents to provide oil removal/control properties to the skin. The invention further encompasses the use of polymer based cleansing systems to optionally deposit, for example, hydrophilic emollient and/or humectant components, and to provide moisturization and hydration properties to the skin.